Superheater.



No. 771,324. PATENTED OCT. 4, 1904.

F. 1). POTTER. SUP EATER.

APPLICATION 1 ED JAN. 11, 1904.

N0 MODEL: 4 SHEETS-SHEET 1.

M 351 fitter/14213 4 N0. 771,324i PATENTED OUT. 4, 1904.

v F. D. POTTER.

SUPERHEATER.

APPLICATION FILED JAN. 11, 1904.

no 11011111.. v 4 sums-sum a.

No. 771,324. PATENTED OCT. 4, 1904.

. POTTER.

IIIIIIIIIIIIIIIIIIIIIIIIIII 4. N 0 M 0 D E L 4 s H E B T s s H E B T 4.

ill! J mil IHHIHHIIHHIIHHIHHIIH,

55% 2%? fig HIHHHHHHHIIIIIIIHHHH UNITED STATES Patented October 4, 1904.

PATENT OFFICE.

SUPERHEATER.

SPECIFICATION forming part of Letters Patent No. 771,324, dated October4, 1904.

Application filed January 11, 1904. Serial No. 188,527. No model.)

To all whom, it may concern:

Be it known that I, FREDERIC D. POTTER, a citizen of the United States,residing in Linden,Union county, in the State of New Jersey, haveinvented a certain new and useful Improvement in Superheaters, of whichthe fol- 1 lowing is a specification.

This invention has relation to means for superheating steam whetherapplied in combination with the regular steam-generating means orwhether employed in connection with separate superheaters. In thefollowing specification the application of my invention to separatesuperheaters is specifically described.

The principal object to be attained by the use of this invention is theapplication of the hot gases to the pipes containing the steam in such amanner that the coolest steam is subjected to the action of the gases attheir hottest or when they are just leaving the fire-bars, While thesame gases are brought in contact with the pipes containing the morehighlyheated steam after said gases have parted with some of the heatwith which they are charged on leaving the fire. This is so accomplishedas to secure safety of the tubes from burning by the proper initialcooling of the gases as they begin the operation of superheating; but itis one object of this invention to use these gases after they have thussuffered their initial drop of temperature, so that as nearly aspossible a uniform rate of transmission of heat will be obtained, thusmaking all parts of the superheating system equally efficient.

I attain the above ends without the necessity of passing the steamthrough any dead length of pipe and without the introduction of bends,elbows, or joints in the steam-pipes. The gases themselves are sodirected in my device as to accommodate the ends above stated withpractically straight superheating tubes.

One preferred means employed by me for carrying out my invention isshown in the accompanying drawings, wherein Figure 1 is a longitudinalsection of one side of a double superheater. Fig. 2 is a horizontalsection of the same above the piping. Fig. 3 is a cross-section of thesame, taken on the line a 6 of Fig. 2; and Fig. 4: is a similarcross-section showing a modification.

In the form shown in Figs. 1 to 3, inclusive, the main steam-inlet isshown at 1 and the main steam-outlet at 2. This is preferably combined,as shown, with a double superheating system comprising four drums at therear end of the device and two drums at the front end. In one system thesteam enters by the branch pipe 3 to the upper drum 4, thence forward bythe superheating-pipes 5 to the upper cross-drum 6,'thence back again bythe superheating-pipes 7 to the upper short drum 8, and out by thebranch pipe 9. A similar circulation occurs through the branch pipe 10,the drum 11,superl1eater-pipes l2, crossdrum 13, superheater-pipes 14,lower short drum 15, and branch pipe 16. The superheater-pipes 5 and 12are contained in the chambers 17 and 18 and the superheater-pipes 7 and1 1 in the chambers 19 and 20. The grate-bars 21 are placed under anarched roof 22, separating the fire-space and the chamber 23 from thechambers 20 and 19, respectively. In the form shown in these figures thecharmbers 17 and 18 extend from top to bottom of the superheater, whilethe chambers 19 and 20 are confined between the arch 22 and the roof 24.The chambers 17 and 18 are separated entirely (except through chambers19 and 20) by means of a partition-wall of fire-brick or otherappropriate material. (Shown in dotted lines at 25 and 26 in Figs. 1 and2.) The hot gases leaving the grate-bars 21 pass into the chamber 23 andout through the opening 27 into the lower part of the chamber 17. Thencethey pass upward in contact with the coolest portions of the steam-pipes5 and 12 and out of the chamber 17 into the chamber 19 through theopenings 28. Thence they pass down over the hottest portion of thesuperheating-pipes and under the downwardly-extending deflecting-wall 29into the chamber 20. Here the gases rise and pass over a somewhat lesshot down over those portions of the super-heaterpipes which (next tothose portions first met by the gases) are the coolest. Passing downover these pipes 5 and 12 the gases finally take their exit through theopening 31. (Shown in Fig. 3.) It will thus be seen that theintensely-hot gases which would otherwise tend to burn out thesteampipes are first brought in contact with the coolest of the pipesand are brought to a temperature sufficiently low, so that they do notendanger the hottest of the superheating-pipes. Having been brought tothis safe temperature, the best results are produced by causing thegases so tempered'td movein an opposite direction to the steam, or, inother words, so that as the gases cool by virtue of loss of heat to thesteam they come successively into contact with cooler and cooler steampipes. This maintains an approximately equal difference of temperaturebetween the gases and the steam and secures a more uniform transmissionof heat than would otherwise be the case. It will be seen from the abovedescriptions and the drawings that this is precisely the condition whichis attained by my arrangement.

1n the form shown in Fig. 4 my invention is adapted to use with twofire-grates. (Shown, respectively, at 21 and 32.) Here the chambers 17and 18 do not extend from the top to bottom of the superheater, but areseparated from the fire-space below by the arched wall 33. In this formthe opening 31 is placed above the wall 38 and the partition-wall 25 isomitted. The opening 27 thus unites the rear ends of two fire-spaces,and of these that shown on the left in Fig. 4: opens directly upwardupon the superheater-pipes 5 and 12.

A variety of changes might be made by those skilled in the art in thearrangements hereinbefore shown anddescribed without departing from thespirit of my invention, and 1 am not to be understood as limiting myselfto the details so shown and described.

What 1 claim is- 1. In a superheater, steam-pipes, means for producinghot gases and means for leading said gases first to the coolest part ofsaid steampipe and thence from the hottest to the coolest part oftheremainder of said pipes, substantially as described.

2. In a superheater, a furnace, a group of superheating-pipes andpassages for leading hot gases from said furnace first to the coolestportion of said pipes, thence to the hottest portions of said pipes andthence to suecessively cooler portions of the pipes, substantially asdescribed.

3. In a superheater, four chambers for receiving hot gases,superheating-pipes leading from the source of steam across two of saidchambers, superheating-pipes leading from said first-named pipes acrossthe other two chambers, a furnace and means for leading hot gases fromsaid furnace first into that chamber nearest the source of steam, nextinto the chamber farthest from the source of steam, next into the thirdchamber from the source of steam and lastly into the second chamber fromthe source of steam, substantially as described.

4. In a superheater, a furnace and agroup of four chambers built oversaid furnace in combination with superheating-pipes leading from thesource of steam forward through two of said four chambers, another setof pipes leading from the end of said first pipes back through the othertwo chambers to an outlet and means for leading the hot gases from saidfurnace upward through the chamber nearest the source of steam, thencedownward through the chamber farthest from the source of steam, thenceupward through the chamber third from the source of steam, and thencedownward through the chamber second from the source of steam,substantially as described.

5. In a superheater and in combination with a furnace, two pairs ofchambers side by side above said furnace a short drum at the rear end ofeach rear chamber and a crossdrum connecting the front ends of the frontchambers and superheating-pipes connecting each short drum with one endof said cross-drum.

6. In a superheater, two pairs of chambers side by side a short drum atthe rear end of the rear chamber in each pair, a cross-drum connectingthe front end of the front chamber of each bar, superheating-pipesconnecting each drum with one end of said crossdrum, a furnace and meansfor leading the gases from said furnace first into the chambercontaining one of said short drums thence into the chamber containingthe other short drum, thence into the next forward chamber and thenceinto the last remaining chamber, substantially as described.

FREDERIC D. POTTER.

llVitnesses:

HAROLD S. MAOKAYE, FLORENCE Prcx.

